strlcpy.c revision 126274 
1/* OPENBSD ORIGINAL: lib/libc/string/strlcpy.c */
2
3/*	$OpenBSD: strlcpy.c,v 1.8 2003/06/17 21:56:24 millert Exp $	*/
4
5/*
6 * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
7 *
8 * Permission to use, copy, modify, and distribute this software for any
9 * purpose with or without fee is hereby granted, provided that the above
10 * copyright notice and this permission notice appear in all copies.
11 *
12 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
13 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
14 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
15 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
16 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19 */
20
21#include "includes.h"
22#ifndef HAVE_STRLCPY
23
24#if defined(LIBC_SCCS) && !defined(lint)
25static char *rcsid = "$OpenBSD: strlcpy.c,v 1.8 2003/06/17 21:56:24 millert Exp $";
26#endif /* LIBC_SCCS and not lint */
27
28#include <sys/types.h>
29#include <string.h>
30
31/*
32 * Copy src to string dst of size siz.  At most siz-1 characters
33 * will be copied.  Always NUL terminates (unless siz == 0).
34 * Returns strlen(src); if retval >= siz, truncation occurred.
35 */
36size_t
37strlcpy(char *dst, const char *src, size_t siz)
38{
39	register char *d = dst;
40	register const char *s = src;
41	register size_t n = siz;
42
43	/* Copy as many bytes as will fit */
44	if (n != 0 && --n != 0) {
45		do {
46			if ((*d++ = *s++) == 0)
47				break;
48		} while (--n != 0);
49	}
50
51	/* Not enough room in dst, add NUL and traverse rest of src */
52	if (n == 0) {
53		if (siz != 0)
54			*d = '\0';		/* NUL-terminate dst */
55		while (*s++)
56			;
57	}
58
59	return(s - src - 1);	/* count does not include NUL */
60}
61
62#endif /* !HAVE_STRLCPY */
63